converting to heithsmap

[Rex Invictus]

Does anyone know a way to convert a colored World Wind Earthtopo add-on map to a grayscale heightmap? I have tryed on photoshop with the hue/saturation feuture and i was near but i cant do it.

[Muizer]

a colored World Wind Earthtopo add-on map.

That isn't much to go on really. I've no idea what kind of map that would be.

[Rex Invictus]

It is a colored heithmap. I dont know how to insert screens in to posts. The problem is the colorscale. -11'000m is dark blue -500m is cyan 0 + is green and 5000 is red. I would like to know if it is possible to change this colorscale like: -500 - 0 is black and 5000+ is white?

[vikrant]

shift+ctrl+u
should work

[makanyane]

The shift+ctrl+u will convert it into greyscale in photoshop but I'm not sure that will help a lot as the cyan could come out lighter (higher) than the red. (Think I understand what you were trying to do with hue/saturation but suspect its unlikely that you'd manage to get a smooth transition between the tones across the various colours.)

EDIT: actually how about selecting each colour (hue) separately, getting each onto separate layer, converting all to greyscale, viewing all together then adjusting brightness /contrast for each layer individually till it looks a progression from black to white? Have no idea how realistic it would end up though!

If that doesn't work and unless anyone else has got any inspiration I think you need source information that is either already in black and white or at least just has one colour and uses tone only to show heights.

You could try satellite data see:
http://forums.totalwar.org/vb/showthread.php?t=57828
for some links...

Re: posting images save as jpeg, upload to http://imageshack.us/
or similar and copy and paste the link that gives you (preferably the thumbnail for forums version) into your reply.

[Rex Invictus]

Thanks Makanyane. I will try it. I know about the 3dem data and the world wind software suits me much more because you can roate it without loosing the quality. It has also a Hydro 1k addon were you have all the rivers in europa. And thanks to blue marble data were you can choose a month, you can see were the snow is (good for climates).